using System;
using System.Collections;

using Org.BouncyCastle.Math;

namespace Org.BouncyCastle.Asn1.CryptoPro
{
	public class ECGost3410ParamSetParameters
		: Asn1Encodable
	{
		internal readonly DerInteger p, q, a, b, x, y;

		public static ECGost3410ParamSetParameters GetInstance(
			Asn1TaggedObject	obj,
			bool				explicitly)
		{
			return GetInstance(Asn1Sequence.GetInstance(obj, explicitly));
		}

		public static ECGost3410ParamSetParameters GetInstance(
			object obj)
		{
			if (obj == null || obj is ECGost3410ParamSetParameters)
			{
				return (ECGost3410ParamSetParameters) obj;
			}

			if (obj is Asn1Sequence)
			{
				return new ECGost3410ParamSetParameters((Asn1Sequence) obj);
			}

			throw new ArgumentException("Invalid GOST3410Parameter: " + obj.GetType().Name);
		}

		public ECGost3410ParamSetParameters(
			BigInteger a,
			BigInteger b,
			BigInteger p,
			BigInteger q,
			int        x,
			BigInteger y)
		{
			this.a = new DerInteger(a);
			this.b = new DerInteger(b);
			this.p = new DerInteger(p);
			this.q = new DerInteger(q);
			this.x = new DerInteger(x);
			this.y = new DerInteger(y);
		}

		public ECGost3410ParamSetParameters(
			Asn1Sequence seq)
		{
			if (seq.Count != 6)
				throw new ArgumentException("Wrong number of elements in sequence", "seq");

			this.a = DerInteger.GetInstance(seq[0]);
			this.b = DerInteger.GetInstance(seq[1]);
			this.p = DerInteger.GetInstance(seq[2]);
			this.q = DerInteger.GetInstance(seq[3]);
			this.x = DerInteger.GetInstance(seq[4]);
			this.y = DerInteger.GetInstance(seq[5]);
		}

		public BigInteger P
		{
			get { return p.PositiveValue; }
		}

		public BigInteger Q
		{
			get { return q.PositiveValue; }
		}

		public BigInteger A
		{
			get { return a.PositiveValue; }
		}

		public override Asn1Object ToAsn1Object()
		{
			return new DerSequence(a, b, p, q, x, y);
		}
	}
}
